Accessory for controlling operation of carburetor accelerator pump



Jan. 17, 1967 G. MIANO 3,298,675

ACCESSORY FOR CONTROLLING OPERATION OF CARBURETOR ACCELERATOR PUMP Filed Feb. 20, 19s:

INVENTOR. GEORGE MIANO ATTORNEY.

United States Patent 3,298,675 7 ACCESSORY FOR CONTROLLING OPERATION OF CARBURETOR ACCELERATOR PUMP George Miano, Alhambra, Calif., assign0r,by mesne assignments, to Joseph Miano, Covina, Calif. Filed Feb. 20, 1963, Ser. No. 259,807 1 Claim. (Cl. 261-34) This invention relates to carburetors, and more particularly to a specially constructed accessory substitutable for the conventional operating link between the accelerator pump and the operating linkage for the carburetor throttle valve, and including provision for manually adjusting the length of this operating connection to render the accelerator pump operable and inoperable at the drivers option.

Conventional carburetors for use on motor-propelled vehicles customarily employ an accelerator or booster fuel pump having an operating connection with the control linkage for the carburetor throttle valve. Such fuel pumps serve to augment the supply of fuel to the engine, particularly during starting operations and in driving under conditions having momentary need for extra fuel. Owing to the provision made for operating such pumps by depressing the accelerator pedal, the operator need but pump the accelerator pedal several times while operating the starter motor to provide a substantially instantaneous and ample fuel supply to expedite motor starting. Once the engine is started and operating at a given speed fuel supply is controlled in accordance with other design characteristics and normal functioning of the carburetor. However, each time the accelerator pedal is depressed from its retracted position, the plunger of the accelerator pump is unavoidably depressed and acts to jet extra fuel into the carburetor in addition to that normally supplied. A considerable portion of the additional fuel supplied in this manner may be and usually is in excess of actual requirements and represents a net fuel loss as well as the supply of power beyond that actually required. In consequence urban driving and the like involving frequent starting, stopping and accelerating unavoidably results in wastage of fuel. This is also true with respect to driving in crowded traflic where frequent and marked change in the rate of travel occurs.

To circumvent such fuel wastage and the resultant needless contamination of the atmosphere with unburned and semi-burned fuel, there is provided by the present invention a simple, easily installed accessory to be used in lieu of the conventional link between the throttle valve operating linkage and the accelerator pump and featuring a device instantly effective to activate and de-activate the accelerator pump at any time merely by manipulating a control button easily accessible to the vehicle driver. This accessory includes an adjustable lost motion connection having flexible cable operating means and a control button therefor readily mountable close to the driver. When the control is at one extremity of its operating range, the accelerator pump operates in the normal way to supply extra fuel to the engine intake manifold, whereas in the second extreme position of the device, the accelerator pump is totally ineffective or de-activated. When adjusted to intermediate positions between these two extreme positions, the fuel pump is rendered more or less effective to the extent desired to meet particular operating conditions, a feature not heretofore available.

Accordingly, it is a primary object of the present invention to provide simple and effective means for adjusting the output of a carburetor accelerator pump at any time during operation of the vehicle through control means readily accessible to the vehicle driver while driving the vehicle.

3,298,675 Patented Jan. 17, 1967 "ice Another object of the invention is the provision of an accessory device easily attachable to vehicle carburetors by the novice and including control means installable near the vehicle drivers position enabling the driver to regulate, activate, and de-activate the carburetor accelerator pump at will.

Another object of the invention is the provision of the simple unitary accessory attachable to conventional vehicle carburetors in lieu of the operating linkage between the accelerator pump and the throttle valve operator and by means of which the vehicle driver can adjust the operating effectiveness of the accelerator pump while driving the vehicle.

These and other more specific objects will appear upon reading the following specification and claims and upon considering in connection therewith the attached drawing to which they relate.

Referring now to the drawing in which a preferred embodiment of the invention is illustrated:

FIGURE 1 is an elevational view of a fuel carburetor having the present accelerator pump control accessory installed therein;

FIGURE 2 is a fragmentary longitudinal sectional view on an enlarged scale through the lost motion connection of the invention device; and

FIGURE 3 is a fragmentary cross-sectional view on an enlarged scale taken along line 33, on FIGURE 2.

Referring more particularly to FIGURE 1, there is shown a conventional fuel carburetor; designated generally 10, of a type commonly used to supply fuel and air to the intake manifold of a vehicle engine. Inasmuch as the constructional details of such carbuertors are well known, it will not be necessary to illustrate and describe these details. In accordance with conventional practice an air filtering device of suitable construction will be understood. as mounted about annular flange 11 surrounding the upper end of the inlet to a venturi tube 12 extending vertically through the carburetor. The lower discharge end of this venturi is in direct communication with the engine intake manifold and conveys a proper mixture of fuel and air thereto as formed in venturi 12. The flow of this fuel mixture into the intake manifold is controlled by the usual butterfly type throttle valve (not shown) and having a horizontally positioned operating shaft 13 journaled crosswise of the venturi and having operating cranks 14, 14' mounted on its opposite outer ends. In accordance with customary practice, crank 14 is connected by an operating linkage (not shown) extending to an accelerator pedal pivotally supported on the floor of the drivers compartment. Crank 14 on the other end is usually connected to the accelerator pump in a manner to be described presently.

Mounted along the side of the carburetor is a housing 16 enclosing any suitable accelerator pump construction, a typical embodiment of which is illustrated in some detail in FIGURE 3. As there shown, the pump comprises a vertically disposed pump cylinder 18 reciprocally supporting a piston 19 having an operating piston rod 20 projecting throughthe upper end of the cylinder. A light compression spring 22 normally urges the piston upwardly and, in so doing, acts to charge the lower end of cylinder 18 with fuel through a supply passage 29. The upper end of rod 20 is connected through a link 23 to a crank 24 secured to a shaft 25 journalled in the side wall of the accelerator pump housing. Rigidly secured to the brated orifice fitting 31 in communication with an axial bore extending along a fuel inductor fitting 33 opening downwardly into venturi tube 12 at a point upstream from or closely associated with venturi throat 34. The fuel metering jets are normally flooded by a float valve or liquid fuel level control means of any suitable construction. In consequence of the lower pressure existing in the venturi when the motor is in operation fuel is elevated through the metering jets and through fitting 33 into the venturi tube. As is well known to persons familiar with Vehicle carburetors, lowering of the accelerator piston 19 at any time is effective to discharge the fuel there below upwardly alongthe passage 29 forcing this fuel past the metering orifice and through fitting 33 into the venturi. If the piston is allowed to return to its upper position under the action of spring 22, a new charge of fuel is immediately drawn into the pump chamber through passage 29 thereby recharging the pump in instant readiness to again discharge its contents into the venturi upon depression of piston 19.

Normally operation of the accelerator pump is accomplished by a rigid link having one end journalled in the outer end of throttle valve crank 14 and its other end journalled in opening 27 of the accelerator pump crank 26. As herein shown, this conventional operating link has been detached and there has been substituted in lieu thereof the control accessory designated generally 40 and constituting an important feature of this invention.

The details of accessory 40 are best shown in FIGURE 2 wherein it is seen to comprise a tube 41 secured at its lower end to an operating rod 42 by a set screw 43. The hooked lower end 44 of this rod is held seated in crank 14 by a spring keeper 45. Freely and loosely slidable in the tube 41 is a plunger 46 secured to a rod 47 by a set screw 48. The upper hooked end 49 is journalled in crank 26 and held assembled therein by a cotter pin 50. A threaded stud 55 projects from the side of plunger 46 and through an elongated slot 56 formed lengthwise of tube 41.

Suitable operating means 60 for the described lost motion connection comprises a Bowden wire assembly having an outer flexible housing 62 one end of which is an; chored in a tab 63 projecting from tube 41 enclosing the upper end of slot 56. The other end of the flexible housing 62 is anchored in a threaded tube 64 secured by jam nuts 65 to a mounting bracket 66 securable to the dashboard or the like of a motor vehicle. Extending through FIGURE 1.

attached end of the Bowden wire 62 along therewith. This does not interfere with the adjustment of the Bowden wire or of the knob axially of tube 64 owing to the friction prevailing between and the close fitting rod housed therewithin and supporting knob 69. Accordingly, so long as the parts are in this position the operator has full control of the accelerator pump in the usual manner and can augment the fuel supply by the requisite repeated operation of the accelerator pedal.

Let it now be assumed that the engine is in operation and has warmed sufliciently to avoid need for the accelerator pump. To deactivate the pump for normal driving the driver merely pushes the control knob inwardly to the full line position shown in FIGURE 1 thereby shifting core wire 68 inwardly along flexible housing 62 with its hooked lower end 69 positioned as shown in In these circumstances stud 55 and the attached plunger 46 are positioned closely adjacent the lower end of tube 41. When so positioned, the carburetor throttle valve can be operated freely and in the usual manner by the vehicle operator without operating the accelerator pump. This is because the lost motion device 40 then permits tube 41 to reciprocate lengthwise of stationary plunger 46 without imparting movement to rod 47 or the accelerator pump. The lower end of Bowden wire assembly attached to tube 41 flexes readily and moves bodily along with its supporting lug 63 as plunger 46 7 remains stationary under the influence of spring 22 within housing 62 is a flexible piano wire 68 having a hooked lower end 69 extending loosely through an opening 70 crosswise of stud 55. The upper end of core wire 68 is secured to a rod having a snug frictional fit within mounting tube 64 and having a pull knob 69 secured to its outer end.

The operation of the described device will be quite apparent from the foregoing detailed description of the structure. When the parts of lost motion connecting link 40 are in the position shown in full lines in FIGURE 2 with control knob 69 pulled outwardly away from jam nuts 65, it will be quite apparent that the operating linkage between throttle valve shaft 13 and accelerator pump 25 is adjusted to its maximum length. The parts are held firmly in this position by reason of the friction between Bowden wire casing 62 and the movable components housed thereby. Accordingly and under these circumstances operation of the accelerator pedal (not shown) in the drivers operating compartment will rotate the throttle valve in a direction to produce a flow of fuel into the engine intake manifold and will also rotate crank 14 and to move link 42, tube 41, plunger 46, and rod 47 upwardly. This movement rotates crank 26 counterclockwise (as viewed in FIGURE 3) and depresses piston 19 and thereby forcing the charge of fuel therebelow into the carburetor venturi by way of passage 29, orifice fitting 31, and fitting at 33. During this operation rods 42, 47 move bodily upwardly, and, in so doing, carry the the accelerator pump. To be noted is the fact that the area opening 70 in stud 55 moves freely along the exposed end of core wire 68.

If the operator pulls outwardly on knob 69 to shorten the exposed lower or remote end of wire 68, the amount of lost motion between plunger 46 and tube 41 is decreased by an amount depending upon the distance knob 69 is pulled away from jam nut 65. Under these conditions, full depression of the accelerator pedal operates the accelerator pump through a short stroke. Normally it is not desired to adjust the knob to intermediate positions and the operator places the knob either against jam nut 65 in which position the accelerator pump is fully deactivated, or he pulls the knob out until the hooked end 69 of wire 68 pulls stud 55 against tab 63 in which event the accelerator pump is fully activated and operates in the same manner as though accessory 40 were replaced with the usual continuous operating link between throttle valve crank 14 and the accelerator pump.

While the particular accessory for controlling the operation of a carburetor accelerator pump herein shown and disclosed in detail is fully capable of attaining the objects and providing the advantages hereinbefore stated, it is to be understood that it is merely illustrative of the presently preferred embodiment of the invention and that no limitations are intended to the details of construction or design herein shown other than as defined in the appended claim.

I claim:

An accessory device adapted to be connected between a vehicle carburetor accelerator pump and the control linkage of the carburetor throttle valve and adjustable to activate and de-activate the accelerator pump at the drivers option and according to the need or lack of need for operating the accelerator pump, said device comprising a pair of concentrically-related axially-movable elements one of which is connectable to the accelerator pump and the other to the operating linkage for the carburetor throttle valve, and operator controlled means coupled between said pair of elements and operable by the vehicle driver while driving the vehicle to vary the eflective length of the operating connection between throttle valve operating linkage and the accelerator pump and including means for holding said elements in a desired adjusted position, said operator con-trolled means comprising a Bowden wire assembly having a core wire encased in a flexible tubular housing anchored at one end to one of said elements and anchored at its other end to a fixed support adjacent the vehicle driver, said core wire having lost motion connection means with the other of said pair of elements and having an operating handle at its other end accessible to the vehicle driver.

References Cited by the Examiner UNITED STATES PATENTS 2,007,197 7/1935 Hedblom 103-38 2,148,112 2/ 1939 Dillstrom 10338 2,183,636 12/1939 Berry 26134 6 Seymour 26134 Harper 10338 Weber 26134 Wallace 103--38 Boyce 26134 Johnson 10338 Scholin 10338 HARRY B. THORNTON, Primary Examiner. 10 T. R. MILES, Assistant Examiner. 

